A New Interpretation of Substantial Motion on the Ground of Essential Knowledge of Natures

The relation between stable and changing is among difficult philosophical cruxes on which philosophers were interested in from the ancient times. Mulla Sadra also، according to his argument of substantial motion and what follows from that، has grappled with that problem from another point of view. But there is still some ambiguity in his explanation and articulation of the problem. Among them is the problem how substantial motion can be held consistently with the stability of Dahr world، which Mulla Sadra believes in. in this paper we try to put a further gloss on substantial motion and clarify these ambiguities by assuming a different assumption. This later assumption، considers important the role of material beings in realization of substantial movement. But due to the fact that there is a lot of disputation on the possibility of realization of knowledge in material beings among philosophers، we first embark solving such debates and defending the possibility of realization of knowledge in material natures and afterwards on the ground of it، we elaborate substantial motion. Also scrutinizing the relation between Dahr world with material universe and establishing the unity of these worlds، and denying causal relation between them، we''ll establish their subjective duality and on the ground of that، we''ll elaborate the fact how one can hold consistently the substantial motion of material world vis-à-vis the stability of natures in Dahr world.